[rthiggins]

Hi everyone, I'm hoping that my problem will seem obvious to someone here!

I just installed a Speeduino on a Cadillac 425. I used a Holley 2 barrel TBI on it. I'm using stock GM sensors, the stock HEI distributor, and a spartan wideband 02 sensor. I'm only using Speeduino for fuel injection at the moment and plan to add the spark functionality later.

I'm ready to fire it up and the injectors don't seem to be opening. I've verified that the fuel pump runs for the priming pulse and that fuel is making it to the injectors. My CLT, IAT, MAP, and TPS sensors are registering in Tuner Studio and I think I have everything set up right in tuner studio including importing a base tune. I'm running the HEI tach signal to RPM input one and have the VR module and can see the tach bump up while cranking in tuner studio. My injectors measure about 1.3 Ohms resistance and I added 6 Ohm 25 watt resistors in series with them on the ground side of the injectors. I checked and with the ignition on and I have 12 volts on the resistors so the injectors are getting power. Still I'm not seeing the injectors open when I'm cranking. I didn't connect anything to the Cam sensor since I'm using the distributor for my tach signal and I have it configured for distributor in tuner studio. The other thing I'm wondering is if there is a polarity on these particular injectors. I know most injectors don't care about polarity. I hooked them up identically. The connectors on them are keyed so that they only go on one way.

Do I need to have something connected to the cam sensor input for my application?
I'm wondering if my series resistors are too big on the injectors?
Did I miss some configuration in tuner studio?
Do my injectors need to be connected with a specific polarity and I have them backwards?

Any help would be appreciated.

[dazq]

Try enabling hardware test mode and see if the injectors will fire manually .
Please be careful as it's very easy to flood the engine or cause hydraulic lock by filling the bores up. Best to disconnect the pump whilst testing this way to minimise fuel feed.

[rthiggins]

Will do. Thanks for the tip.

[theonewithin]

Also please post a log and your tune.

[LPG2CV]

Are your injector LEDs flashing when cranking. If you are not using all of the injection channels, are the ones you are using, the ones you have connected?

[rthiggins]

All of the injector LEDs are blinking while cranking though I only have two channels connected, one for each of the injectors.

[LPG2CV]

Time to post your tune

When your cranking, is your foot off the accelerator pedal?

[Torslund]

You should see if the injectors squirts, just look down in the TB. Remove one spark plug and look if it is wet. Turn off fuel and use engine starter spray, if fires you have spark. 6ohm in series with injector, do you get enough current for the injector?

[rthiggins]

I'm uploading logs from cranking and a current tune file. I'm still learning to interpret them.

[rthiggins]

I have my series resistors after the injectors on my install. With the ignition on, a jumper to ground between the resistor and ground would fire the injector, but after the resister wouldn't. Dropping the value of the resistor to 5 Ohm did the trick and I was able to fire the injector from the hardware test interface which I couldn't before.

I know I have ignition because pouring a bit of gas down the intake will make the engine fire and sputter.

I'm still not seeing the injetors fire while cranking though. One other thing, all the LEDs on the injector channels are firing while cranking. Is that supposed to happen or just the two I have connected? I'm starting to suspect that I have a configuration problem here.